APA

United States Geological Survey N. E. I. C., . (2006). Preliminary earthquake report: Magnitud 4.0 al Oeste de las Islas Galapagos. Denver, Colorado, USA: United States Geological Survey, National Earthquake Information Center.

Chicago

United States Geological Survey National Earthquake Information Center, . 2006. Preliminary earthquake report: Magnitud 4.0 al Oeste de las Islas Galapagos. Denver, Colorado, USA: United States Geological Survey, National Earthquake Information Center.

Harvard

United States Geological Survey N. E. I. C., . (2006). Preliminary earthquake report: Magnitud 4.0 al Oeste de las Islas Galapagos. Denver, Colorado, USA: United States Geological Survey, National Earthquake Information Center.

MLA

United States Geological Survey National Earthquake Information Center, . Preliminary earthquake report: Magnitud 4.0 al Oeste de las Islas Galapagos. Denver, Colorado, USA: United States Geological Survey, National Earthquake Information Center. 2006.